‘NCIS’: Meet Mark Harmon’s Son, Sean, Who is Also an Actor

by Jacklyn Krol

Did you know that Mark Harmon’s son is an actor? Meet Sean Harmon.

Sean Harmon is the son of Mark Harmon and Pam Dawber and was born on April 25, 1988.

Harmon is a jack of all trades in the television and film industries. His first non-NCIS role was in 2012. He guest-starred on CSI: NY as Ethan Grohl on the “2,918 Miles” episode.

He has appeared on Haven: Origins, Hold On, Major Crimes, and The Ultimate Evil.

In addition to his NCIS appearances, he crossed over for an episode of NCIS Los Angeles. In 2015, he portrayed the character of Charlie Connor in the “Rage” episode.

Sean Harmon is more than just an actor. In 2012, he served as the writer, director, and producer for his short film Catholic Schoolgirl Chainsaw Showdown. Additionally, he was a stunt double on Dumb and Dumber To and American Reunion. Similarly, he was the stunt coordinator for films like The Sweet Taste of Redemption, Takanakuy, and The Labyrinth. 

In his downtime, he enjoys surfing and kickboxing. Harmon’s upcoming TV film, Thicker, which is set to debut later this year.

The Mark Harmon and Sean Harmon ‘NCIS’ Crossover

Sean Harmon portrayed a young version of Mark Harmon’s character on NCIS, Leroy Jethro Gibbs. His first acting role was in 2008 for the episode “Heartland.” Since then, he has appeared as the younger version of his father in seven episodes through 2020.

Most recently, he portrayed a young version of Mark Harmon in the 2020 episode “Everything Starts Somewhere.”

Mark Harmon spoke about his son’s cameos to Entertainment Tonight last year. He shared that when the team discussed a young Gibbs, Sean had just finished school at that point.

“A director named Tony Wharmby said, ‘Can he come in and read?’ And on his own he did and I’m proud of him taking his work seriously and how he approaches being an actor — not just on this show, [but] just what he has chosen to try to do in his life’s work,” he said.

He added that he is proud of both of his sons. “They work hard at what they do and I’m proud that they get up in the morning and try to do that every day,” he continued.

Dawber is also thrilled to see the father-son duo work together on the small screen.

“More than anything, she’s a mom, and there’s a pride there involved in that,” he added. “Separate from anything as an actor, you hopefully take pride in who people are individually away from any camera just as people, as citizens. And both our boys have done well and hopefully made smart choices and are doing well daily, you know?”